For a youthful convicted jewel thief who insisted he was innocent, a state appeals court in San Francisco offered a life lesson: Sometimes you have to apologize, even if you think you've done nothing wrong.

The object of the court's instruction was a juvenile identified as J.C., who had done some household work for one of his high school teachers in Vallejo. He came to her classroom to help out one day in August 2011 wearing a pendant that she recognized as custom-made jewelry she'd last seen in a hidden box at home, with a value of $3,000 to $4,000.

J.C. told police he had found the pendant while vacuuming several months earlier, picked it up and intended to return it but forgot about it.

A Solano County juvenile court judge, John Ellis, didn't believe him and found that he had committed grand theft. He put J.C. on three years' probation and ordered him to write an apology, of at least 50 words, to his teacher.

J.C. continued to maintain his innocence, and his lawyer argued in his appeal that the compelled apology would violate his constitutional right against having to incriminate himself. But the First District Court of Appeal said an apology doesn't necessarily mean an admission of guilt.

In a 3-0 ruling this week, the court turned to the American Heritage Dictionary, which defines an apology as an expression of regret, and defines regret as "a feeling of sorrow, disappointment, distress, or remorse about something that one wishes could be different."

J.C. can satisfy the dictionary, and the judge's order, the court said, by telling his teacher that he's sorry for what happened to her, with his own explanation of how it happened.